Bearings are typically used as anti-friction units allowing rotation around a shaft and/or housing. Bearings are capable of handling thrust loads and forces up to a predetermined rating. At times, bearings are subject to extreme loading and micro-slipping forces that can cause roller cage failure.
Bearing cages typically consist of an inner ring, an outer ring, and web-like cage bars that connect the rings. The cage bars are created by piercing to provide a pocket for rolling elements. The cage bars retain, separate, and guide rolling elements in bearings circumferentially and axially. Radially, the rolling elements are guided by the pierced ends of the pockets.
Due to the stress on the cage, the cage bars can fracture at the point of connection with the inner ring and/or the outer ring. This is due in large part to the small radii that are required at the corners of the pocket so as to not interfere with the rolling element radius or end configuration. These small radii are stress risers. Also, with existing cage designs the radial guidance of the roiling elements is poor on the rough pierced surface at the ends of the pocket, which may include small cracks that are also stress risers.